Uniwinnicrypt ransomware charges over $550k for file recovery

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The SonicWall Capture Labs threat research team have been tracking a ransomware family named Uniwinnicrypt.  This malware is aimed at large corporations and the operators charge over $550k USD in crypto (Monero and Bitcoin) for file recovery.  A custom chat site hosted on the tOr network is provided by the operators for negotiations with their victims.  However, conversations between the victims and operators are publicly accessible.

 

Infection cycle:

 

Upon infection, code is injected into grpconv.exe, iexpress.exe or write.exe.  This code performs the encryption of files on the system:

 

The extension “.uniwinnicrypt” is appended to all encrypted files.

 

HOW_FIX_FILES.htm is dropped into all directories where files were encrypted.  It contains the following message:

 

The tOr link leads to the following page:

 

After entering the requested information, the following existing conversation between a victim (not us) and the operator can be seen:

 

SonicWall Capture Labs provides protection against this threat via the following signature:

  • GAV: Uniwinnicrypt.RSM (Trojan)

This threat is also detected by SonicWALL Capture ATP w/RTDMI and the Capture Client endpoint solutions.

Security News
The SonicWall Capture Labs Threat Research Team gathers, analyzes and vets cross-vector threat information from the SonicWall Capture Threat network, consisting of global devices and resources, including more than 1 million security sensors in nearly 200 countries and territories. The research team identifies, analyzes, and mitigates critical vulnerabilities and malware daily through in-depth research, which drives protection for all SonicWall customers. In addition to safeguarding networks globally, the research team supports the larger threat intelligence community by releasing weekly deep technical analyses of the most critical threats to small businesses, providing critical knowledge that defenders need to protect their networks.